Radio Receivers
If a FET is used as the first AF amplifier in a transistor receiver, this will have the effect of

Improving the selectivity of the receiver
Reducing the effect of noise at low modulation depths
Improving the effectiveness of the AGC
Reducing the effect of negative-peak clipping

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Radio Receivers
Indicate the false statement in connection with communications receivers.

Variable sensitivity is used to eliminate selective fading
Double conversion is used to improve image rejection
The noise limiter cuts off the receiver’s output during a noise pulse.
A product demodulator could be used for the reception of Morse code.

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Radio Receivers
In a ratio detector

the circuit is the same as in a discriminator, except that the diodes are reversed
the linearity is worse than in phase discriminator
stabilization against signal strength variations is provided
the output is twice that obtainable from a similar phase discriminator

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Radio Receivers
Indicate the false statement. Noting that no carrier is transmitter with J3E, we see that

The transmission is not compatible with A3E
Production of AGC is a rather complicated process
Adjacent-channel rejection is more difficult
The receiver cannot use a phase comparator for AFC

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